| Firemore Trading Limited | Wholesale & retail | 2020 |
| Fireproper Limited | Real estate | 1986 |
| Firesafety.Uk.Com Limited | Extraterritorial | 2020 |
| Firespider Ltd | Information & communication | 2012 |
| Firoza Pro Ltd | Real estate | 2023 |
| First 4 GAS Limited | Construction | 2017 |
| First 4 H&S Training Limited | Education | 2018 |
| First Avenue Group Limited | Information & communication | 2018 |
| First Aviation Ltd | Transport & logistics | 2025 |
| First Base (UK) Limited | Real estate | 2003 |
| First Care Direct Limited | Health & social care | 2011 |
| First Choice Financial Services Limited | Transport & logistics | 2023 |
| First Choice Hotels Ltd | Hospitality | 2018 |
| First Choice JSO Engineering Ltd | Professional & scientific | 2026 |
| First Choice Meat and Poultry Supplies Ltd | Wholesale & retail | 2026 |
| First Choice Recovery Group Ltd | Wholesale & retail | 2020 |
| First Choice Roofing Ltd | Construction | 2022 |
| First Choice Support Ltd | Health & social care | 2026 |
| First Class Construction Cleaning Ltd | Administrative & support | 2025 |
| First Conference Estate Limited | Hospitality | 1910 |
| First Energy Solutions Limited | Professional & scientific | 2005 |
| First Friends Holdings Ltd | Financial services | 2022 |
| First Friends OUT of School Club Limited | Education | 2026 |
| First Grace Ltd | Health & social care | 2019 |
| First Green Trading Limited | Other services | 2022 |
| First Light Leads Ltd | Professional & scientific | 2013 |
| First Procurement Associates Limited | Administrative & support | 2000 |
| First Procurement Limited | Administrative & support | 1996 |
| First Quality Solutions Ltd | Administrative & support | 1999 |
| First Silicon Consulting Ltd | Professional & scientific | 2023 |
| First Stage Property Ltd | Real estate | 2005 |
| FIRST2SOURCE Ltd | Real estate | 2021 |
| FIRST2SOURCE Maintenance Ltd | Households | 2021 |
| Firstcall Corporation Ltd | Wholesale & retail | 2009 |
| Fish Anchor Limited | Wholesale & retail | 2023 |
| Fish Media Limited | Information & communication | 2003 |
| Fishbone Energy Solutions Ltd | Manufacturing | 2015 |
| Fishbone Logistics Ltd | Professional & scientific | 2023 |
| Fishbone Solutions Group Ltd | Manufacturing | 2010 |
| Fisher Fisher Ltd | Real estate | 2020 |
| Fisher Group Holdings Limited | Financial services | 2026 |
| Fisher Tomlin & Bowyer Limited | Administrative & support | 2004 |
| Fishers Yard Investments Limited | Real estate | 2025 |
| Fiskovan Ltd | Transport & logistics | 2023 |
| Fit Body Bristol LLP | | 2019 |
| Fit Body Training Ltd | Arts & recreation | 2024 |
| Fit POT Limited | Manufacturing | 2024 |
| Fitandfunshop Ltd | Wholesale & retail | 2026 |
| Fitchett Associates Ltd | Real estate | 2025 |
| Fitness for Limited | Professional & scientific | 2003 |
| Fitness, Travel & Security Ltd | Administrative & support | 2025 |
| Fitnsupport Ltd | Wholesale & retail | 2022 |
| Fitout Assist UK Limited | Professional & scientific | 2021 |
| Fitz & Co Ltd | Financial services | 2013 |
| Fitzhugh & Sons Piling Solutions Ltd | Construction | 2017 |
| Fitzy's Barbershop Limited | Other services | 2002 |
| Five Forty Five Limited | Administrative & support | 2011 |
| Five Lamps Auto Centre Limited | Wholesale & retail | 2015 |
| Five Lamps Court (1-10) RTM Company Ltd | Households | 2016 |
| Five Lamps Court (11-26) RTM Company Ltd | Households | 2016 |
| Five Lamps Fish Bar Ltd | Hospitality | 2024 |
| Five Lamps Podiatry Clinic Ltd | Health & social care | 2023 |
| Five Leaves Limited | Information & communication | 1995 |
| Five One Two (E.M.A.) Limited | Transport & logistics | 1988 |
| Five Rivers Live Catering Ltd | Hospitality | 2023 |
| FIX My Legals Limited | Administrative & support | 2022 |
| Fixd FM Limited | Other services | 2024 |
| FIZ Derby Limited | Wholesale & retail | 2024 |
| FJ Day Ltd | Other services | 2019 |
| FJ Enterprises Limited | Wholesale & retail | 2018 |
| FJ Property Ltd | Real estate | 2025 |
| FJ Wholesale Limited | Wholesale & retail | 2026 |
| Fknn Limited | Administrative & support | 2025 |
| FKR Solutions Ltd | Professional & scientific | 2025 |
| Flames and Fame Ltd | Arts & recreation | 2022 |
| Flamingo Glass and Mosaic Art Limited | Education | 2024 |
| Flamingo Health and Social Care Ltd | Administrative & support | 2020 |
| Flash-Over Ltd | Construction | 2019 |
| Flat Meadow Farm Ltd | Real estate | 2015 |
| Flatirons Solutions Limited | Information & communication | 2013 |
| Flavas 4 U Ltd | Wholesale & retail | 2019 |
| Flavourfulevents Ltd | Hospitality | 2023 |
| Flawless Horizon Limited | Financial services | 2024 |
| Fleet Drive Limited | Professional & scientific | 2018 |
| Fleet Express Derby Ltd | Transport & logistics | 2016 |
| Fleet Force Solution Ltd | Transport & logistics | 2024 |
| Fleetcare Road Transport Engineering Ltd | Wholesale & retail | 2002 |
| Fleetchoice Limited | Administrative & support | 2009 |
| Fleetory Ltd | Transport & logistics | 2025 |
| Fleischhacker UK LLP | | 2020 |
| Fleming Control System Consultancy Limited | Professional & scientific | 2008 |
| Fletcher Brickwork Ltd | Construction | 2016 |
| Fletcher Civils and Surfacing Ltd | Construction | 2015 |
| Fletcher Evan Property Management Limited | Households | 2020 |
| Fletcher Heritage Investments Ltd | Real estate | 2026 |
| Fletcher Property Company Limited | Real estate | 2024 |
| Fletchers Timber Derby Limited | Wholesale & retail | 1998 |
| Fletes Services Limited | Financial services | 2024 |
| Fleur.Occasionz Limited | Wholesale & retail | 2025 |
| Flex and Co. Consultants Ltd | Administrative & support | 2026 |